Abstract: A measuring instrument includes a first temperature sensor, a second temperature sensor and circuitry. The first and second temperature sensors each generate a signal indicative of the temperature of a medium being detected. The circuitry is configured to activate verification of temperature being sensed with the first sensor. According to one construction, the first temperature sensor comprises at least one thermocouple temperature sensor and the second temperature sensor comprises an optical temperature sensor, each sensor measuring temperature over the same range of temperature, but using a different physical phenomena. Also according to one construction, the circuitry comprises a computer configured to detect failure of one of the thermocouples by comparing temperature of the optical temperature sensor with each of the thermocouple temperature sensors. Even further, an output control signal is generated via a fuzzy inference machine and control apparatus.

Abstract: A measuring instrument includes a first temperature sensor, a second temperature sensor and circuitry. The first and second temperature sensors each generate a signal indicative of the temperature of a medium being detected. The circuitry is configured to activate verification of temperature being sensed with the first sensor. According to one construction, the first temperature sensor comprises at least one thermocouple temperature sensor and the second temperature sensor comprises an optical temperature sensor, each sensor measuring temperature over the same range of temperature, but using a different physical phenomena. Also according to one construction, the circuitry comprises a computer configured to detect failure of one of the thermocouples by comparing temperature of the optical temperature sensor with each of the thermocouple temperature sensors. Even further, an output control signal is generated via a fuzzy inference machine and control apparatus.

Abstract: A measuring instrument includes a first temperature sensor, a second temperature sensor and circuitry. The first and second temperature sensors each generate a signal indicative of the temperature of a medium being detected. The circuitry is configured to activate verification of temperature being sensed with the first sensor. According to one construction, the first temperature sensor comprises at least one thermocouple temperature sensor and the second temperature sensor comprises an optical temperature sensor, each sensor measuring temperature over the same range of temperature, but using a different physical phenomena. Also according to one construction, the circuitry comprises a computer configured to detect failure of one of the thermocouples by comparing temperature of the optical temperature sensor with each of the thermocouple temperature sensors. Even further, an output control signal is generated via a fuzzy inference machine and control apparatus.

Abstract: A device and method for monitoring the condition of a thermocouple. In a preferred embodiment the device comprises a pair of thermocouples, each thermocouple comprising first and second thermoelement wires, and a diagnostic element selectively electrically coupled at a junction with one of the thermoelements. In a preferred embodiment, the diagnostic element is selected such that it is more stable at the expected operating temperature range of the thermocouple than the thermoelement wires themselves are. The diagnostic element can be switched into electrical connection with any of the thermoelements forming the thermocouples to thereby define one or more loops. An initial loop resistance is measured and recorded around each of the thermoelement/diagnostic element loops. This initial resistance is stored in a calibration matrix as a reference value. The initial loop resistance may be taken as part of a calibration process or during initial operation of the thermocouple.

Abstract: A self-verifying temperature sensor and method for measuring and verifying the true thermodynamic temperature of a system. The sensor is constructed of various combinations of the following temperature-dependent elements: thermoelements, resistive elements, capacitive elements and other inductive elements. In the preferred embodiment, the sensor is constructed of resistive element connected between four thermoelement wires. A fifth thermoelement wire is connected to the resistive element. The sensor produces a data signature from various voltage, resistance, inductance, and capacitance measurements. Measurement electronics collect and condition the data signature. A computer analyzes the data signature and provides the system operator with a verified sensor temperature, thus, allowing the system operator to recognize and account for drift or decalibration of the sensor.

Abstract: A self-verifying temperature sensor and method for measuring and verifying the true thermodynamic temperature of a system. The sensor is constructed of various combinations of the following temperature-dependent elements: thermoelements, resistive elements, capacitive elements and other inductive elements. In the preferred embodiment, the sensor is constructed of resistive element connected between four thermoelement wires. A fifth thermoelement wire is connected to the resistive element. The sensor produces a data signature from various voltage, resistance, inductance, and capacitance measurements. Measurement electronics collect and condition the data signature. A computer analyzes the data signature and provides the system operator with a verified sensor temperature, thus, allowing the system operator to recognize and account for drift or decalibration of the sensor.

Abstract: A coaxial, hermetically sealed end structure is described for electrical instrumentation cables. A generally tubular ceramic body is hermetically sealed within a tubular sheath which is in turn sealed to the cable sheath. One end of the elongated tubular ceramic insulator is sealed to a metal end cap. The other end of the elongated tubular insulator has an end surface which is shaped concave relative to a central conductor which extends out of this end surface. When the end seal is hermetically sealed to an instrumentation cable device and the central conductor is maintained at a high positive potential relative to the tubular metal sheath, the electric field between the central conductor and the outer sheath tends to collect electrons from the concave end surface of the insulator. This minimizes breakdown pulse noise generation when instrumentation potentials are applied to the central conductor.

Abstract: An improved coaxial end seal for hermetically sealed nuclear instrumentation cable exhibiting an improved breakdown pulse noise characteristic under high voltage, high temperature conditions. A tubular insulator body has metallized interior and exterior surface portions which are braze sealed to a center conductor and an outer conductive sheath. The end surface of the insulator body which is directed toward the coaxial cable to which it is sealed has a recessed surface portion within which the braze seal material terminates.

Abstract: An improved neutron responsive self-powered radiation detector is disclosed in which the neutron absorptive central emitter has a substantially neutron transmissive conductor collector sheath spaced about the emitter and the space between the emitter and collector sheath is evacuated.